#复习一遍这个程序，并在每一行上面写上注释来解释它。
#找到所有把字符串放在字符串里面的地方，一共有4处。(6)

types_of_people = 10
x = f"There are {types_of_people} types of people."

binary = "binary"
do_not = "don't"
y = f"Those who know {binary} and those who {do_not}."

print(x)
print(y)
print(f"I said: {x}")
print(f"I also said: '{y}'")

hilarious = False
joke_evaluation = "Isn't that joke so funny?! {}"

print(joke_evaluation.format(hilarious))

w = "This is the left side of..."
e = "a string with a right side."
print(w + e)